The invention relates to tissue pathology, and more particularly to systems and methods for screening of biological samples.
Laser scanning cytometry (LSC) is used for detecting and measuring various properties of biological samples. Typically, in LSC, a biological sample is stained with a fluorescent dye. The fluorescent dye binds to a particular constituent of a cell in the biological sample. The stained sample is disposed on a slide. A laser source is used to provide focused laser beam to excite the sample. The laser source is coupled to an objective lens to provide a focused laser beam. Fluorescently marked cells when illuminated by the laser beam emit fluorescent light. A detection device is used to measure a fluorescent intensity of the cells in the biological sample. The fluorescent intensity depends on an amount of the fluorescent dye contained in the cell. Based on the fluorescent intensity an amount of a particular cell constituent in the sample is determined.
Conventionally, in LSC systems a whole slide image is formed by acquiring field by field images of individual zones of the slide and then digitally stitching or tiling the individual images together to form a full image. This process of selecting individual images and stitching or tiling them together is time consuming and labor intensive. Existing LSC techniques require about 3 to 5 minutes for preview scanning of a full slide to provide an initial estimate of the constituents present in the slide. Further, conventional microscopes used in LSC require professional personnel to operate the system. The operation of such microscopes is both time-consuming and labor-intensive.
Conventional epi-fluorescent microscope acquisition methods are typically slow and require about an hour or more to produce an image of a whole tissue slide. The conventional epi-fluorescent microscope systems operate with limited prior knowledge of the location or intensity of fluorescent labeling, thereby making such systems inefficient and time consuming.
Typically, LSC systems are bulky and provide lower flexibility to the user. For example, the LSC systems require a narrow field or focused laser beam for scanning the biological sample. Producing a focused laser beam requires complex optics arrangement, stringent alignment requirements for the optics, thereby adding to the size and inflexible nature of the system. Additionally, in the LSC systems the scanning is time consuming because of the relatively narrow field of view of the focused laser beam. Also, with the narrow field of view of the focused laser beam, the probability of the slide surface moving outside the field of view of the focused laser beam is high. Hence, the cell constituent detection may be less than optimal while using the focused laser beam for scanning.
Therefore, it is desirable to have improved systems and methods for tissue screening that provides to identify regions of interest at a high speed in high content cellular analysis and advanced tissue imaging and analysis. Further, it is desirable to have improved systems and methods for tissue screening that are simple to use and easy to align.